Times Square is loud. But if you turn away from the glowing lights and ignore the cacophony of car horns, barkers, and tourists, you might notice a mysterious drone drifting from the subway grates below. It’s a curious metallic “wah-wah” that resembles a decaying gong, or a didgeridoo player hopelessly trapped in the sewer. It’s what I imagine being sucked into an eternal vortex sounds like.

It’s more than mere mechanical noise. It’s a piece of sound art. Installed in 1977, it was created by artist Max Neuhaus, who aptly titled it “Times Square.” Neuhaus made a machine that amplifies the resonance of the Square’s tunnel junction, exposing an uncanny hum that would otherwise remain muffled underground. Amazingly, he created the cloud of noise without the help of a computer or electronic music.

What’s more amazing, though, is that no one ever notices it’s there. Which is kind of the point. There’s no sign pointing out the work. You can’t find Neuhaus’ name anywhere around. The machine is hidden in the bowels of the tunnels below, and all you can see is a sea of cigarette butts, a metal grate, and upturned noses as people catch a whiff of the New York subway’s aroma du jour.

Neuhaus kept it secret because he wanted people to discover it on their own, to experience that “Hey! Guess what I found!” moment. But it also prompts something worth mulling over: Is it possible to distract someone—even for a moment—from the brightest lights in the biggest city?

Well, try for yourself. You can find the buzz on a concrete island between 45th and 46th Streets, pinched between Broadway and 7th Avenue. There’s a good chance that a creepy costumed Elmo or Mario will mark the spot.